JP2666852B2 - Positive-type radiation-sensitive mixture, positive-type radiation-sensitive recording material and production method thereof - Google Patents

Description

The present invention relates to the manufacture of capacitors, semiconductors, multilayer printed circuits or integrated circuits containing compounds which form acids under the action of actinic radiation and compounds which are decomposable by acids. To a positive-working radiation-sensitive mixture.

Prior art The formation of an acid by the action of actinic radiation on a photopolymerization initiator,
Positive-working radiation-sensitive mixtures in which the acid then dissolves the irradiated area of the acid-decomposable material in a second reaction in a suitable developer have long been known.

Acid decomposable materials conventionally used in the field may include: a) materials containing at least one otorcarboxylic acid ester group and / or carboxamidoacetal group, in which case the compound Has polymer properties and each of the above groups can also occur as a linking element in the backbone or as a side chain substituent; b) oligomers or polymers containing repeating acetal and / or ketal groups in the backbone Compounds, c) compounds containing at least one enol ether or N-acyliminocarbonate group, d) compounds containing silyl ether groups, e) compounds containing silenol ether groups, and f) cyclic β-ketoesters or amides. Acetal or ketal.

The acid-decomposable compounds of type a) as components of the radiation-sensitive mixture are described in detail in EP 0 022 571 and West German patent application EP 2 610 842: Mixtures containing compounds of type b) are described in West German patents 2 306 248 and 2 718 254; compounds of type c) are described in European patent applications 0 006 626 and 0 Compounds belonging to type d) are disclosed in West German Patent Application Publication Nos. 3 544 165 and 3 601 264; compounds of type e) are described on the same day. Compounds of the type f) are described in European Patent Application No. 0 202
No. 196 is cited.

DE-A-2 610 842 describes compounds containing orthoester groups or orthoamide acetal groups in radiation-sensitive copying materials, which produce both printing plates and microelectronic circuits. Used for Alcohol components mentioned for such groups are alkyl, alkenyl and aryl groups. Good results are C ₁ -C ₁₈ - has been reported in an aliphatic alcohol ranges alcohol. It has been pointed out that compounds based on monoalkyl ethers of polyethylene glycol also have comparable properties, in which case the number of ethylene oxide units is in particular from 1 to 8. The results of the study show that if the alcohol component used has a boiling point high enough to prevent evaporation from the irradiated coating,
It has always been shown that good process acceptability is provided. When polyethylene glycol monoalkyl ether was used, it was necessary to use an alcohol component having a relatively high molecular weight, as in the case of using an aliphatic alcohol. These alcohols have drawbacks with regard to their compatibility with the phenolic resins commonly used for such coatings or due to their effectiveness as plasticizers for the resin matrix. The corrosion resistance of the final coating is reduced by the long chain fatty alcohols. This type of coating is therefore only maintained with dissolution losses in the individual processing steps, for example in the production of microelectronic components.

Further, the radiation-sensitive copying material described in DE-A-2 718 254 is used for lithographic printing plates and positive-working resists. These copying materials include (oligomeric) compounds having, as acid-decomposable components, repeating acetal or ketal units whose alcohol component must be at least divalent. In addition to the fact that the molecular weight or the degree of polymerization of this type of polyacetal varies considerably depending on the production process, the danger of contaminants entering the radiation-sensitive mixture is due to the fact that these acid-decomposable compounds can no longer be purified by distillation. Especially critical. Even higher degrees of polymerization in the case of the polymer acetals and ketals described here increase the risk of separation of the used polymers depending on the application conditions. This results in degradation losses, especially when used in the submicron range.

More recently, unlike the state of the art, it has been proposed to use β-keto ester or amide cyclic acetals or ketals as acid-decomposable materials which are also suitable for use in photoresists (European patents Published Application No. 0 202 196). A disadvantage of this photoresist is its low radiation sensitivity.

The problem to be solved by the invention is therefore that the object of the present invention is to make it possible to produce as pure and uniform a shape as possible and to show a change in the development time even when the "stop time" between irradiation and development is different. Therefore, it has a large processing latitude, fulfills the requirements for a high degree of structural decomposition of the developed resist, maintains it during the next processing steps, and also uses an aqueous alkaline developer containing metal ions to An object of the present invention is to obtain a positive-type radiation-sensitive mixture of a type having a uniform and good processability even in the case of containing no.

Means for Solving the Problems This problem is represented by the general formula I: [Wherein R represents a hydrogen atom or an alkyl group, and R ₁ and R ₂ may be the same or different and each represents a hydrogen atom, a hydroxy group, a halogen atom, a cyano group, a nitro group, an alkyl group, an aryl group, or a substituted Represents a carbonyl group, or
R ₁ and R ₂ together form a ring, which may be optionally substituted by R ₁ and / or R ₂ , wherein n is 1-3
A compound formed under the action of an acid from a compound decomposable by an acid as a decomposition product, the compound comprising a compound capable of forming an acid under the action of actinic radiation and a compound decomposable by an acid. The problem is solved by providing a positive-working radiation-sensitive mixture for producing semiconductors, multilayer printed circuits or integrated circuits.

R represents a hydrogen atom or a methyl group, and R ₁ and R ₂ are the same and represent a hydrogen atom, or are different and one of the groups is a hydrogen atom, and the other is a (C ₆ -C ₁₀ ) -aryl Groups, especially phenyl groups, optionally branched (C _1-
C ₈₎ - alkyl, in particular (C ₁ ~C ₄₎ - alkyl, (C ₆
-C ₁₀₎ - arylcarbonyl group, especially a phenyl group or a (C ₁ ~C ₈₎ - alkylcarbonyl group, or a halogen atom, especially bromine or chlorine atom, n is 1
A value of 3 is particularly advantageous. If R ₁ and R ₂ are different and one of the radicals represents a hydrogen atom, the other radical is advantageously in the para-position, wherein R represents a hydrogen atom or a methyl group and n is 1 Represents

When R ₁ and R ₂ are the same and particularly represent a hydrogen atom, R is especially a hydrogen atom or a methyl group, and n is 1-3.

Acetals or ketals whose alcohol component has a boiling point above 200 ° C. at 760 torr or are solid at room temperature are particularly advantageous.

Particularly preferred properties are obtained when unsubstituted compounds of the general formula I are used together with phenyl glycol as alcohol component, where n is 1. .

Acid-decomposable compounds or acetals and ketals derived from aldehydes or ketones and alcohols of the formula I, or orthocarboxylic acid esters and orthocarboxamide acetals, which are used in the radiation-sensitive mixtures according to the invention. Preferred decomposable compounds are those containing one or two acid-decomposable molecular groups, particularly preferably one or more.
It contains one acid-decomposable molecular group per molecule.
Effective purification of the product, for example by distillation means, is ensured when these starting compounds are used.

Acetals and ketals have a boiling point of 155 ° C. or higher and an aqueous solution of 0.1 to 100 g /, as described in West German Patent Application No.P3 730 785.1, on the same day as the carbonyl compounds based on these acetals and ketals. Particularly preferred are those having solubility in an alkali developer in connection with the alcohol component described in the above specification.

The acetal content in the radiation-sensitive mixture according to the invention is in each case 2 to 30% by weight, based on the total weight of the coating, preferably
10 to 25% by weight.

Suitable components of the radiation-sensitive mixture according to the invention which advantageously form or excrete strong acids upon irradiation include a large number of compounds and mixtures thereof.

These include diazonium salts, phosphonium salts, sulfonium salts, iodonium salts, halogen compounds, o-quinonediazidosulfochloride and sulfate, and organometal / organohalogen compositions.

The diazonium compounds, phosphonium compounds, sulfonium compounds and iodonium compounds mentioned above are generally in the form of their salts soluble in organic solvents, often in the form of tetrafluoroboric acid, hexafluorophosphoric acid, hexafluoroantimonic acid and hexafluoroarsenic acid. It is used as a precipitation product with such a complex acid. In particular, these compounds are also described in German Offenlegungsschrift 3,601,264.

Halogen compounds include, among others, U.S. Pat.
552, 3,536 489 and 3,779,778, and West German Patent Nos. 2,718,259, 3,337,024,
No. 3,333,450, No. 2,306,248, No. 2,243,621 and No. 1,298,414. However, these compounds are oxazoles,
It can also be used in combination with other photoinitiators, such as oxadiazole or thiazole, or as an admixture. However, oxazoles, oxadiazoles, thiazoles or 2-pyrones containing trichloromethyl or tribromomethyl groups are also known (West German Patent No. 3).
No. 021 599, No. 3 021 590, No. 2 851 472, No. 2
949 396 and EP 0 135 34
No. 8 and No. 0 135 863).

This generic term also includes aromatic compounds containing ring-bonded halogen atoms, preferably bromine atoms. These compounds are known from German Offenlegungsschrift 2 610 842 or published on the same day in German Offenlegungsschrift P37.
30 748.3.

Representative combinations with thiazoles include those with 2-benzoylmethylene-naphtho [1,2-d] thiazole (West German Patent Application No. 2).
851 641 and 2,934,758). Mixtures of trihalogenmethyl compounds with N-phenylacridone are known from DE-A-2 610 842.

Similarly, α-halogencarboxamides (WO-A-2 718 200) or tribromomethyl-phenylsulfones (WO-A-3 503) which can be sensitized by, for example, benzophenone, benzine or Michler's ketone. No. 113) can also be used.

In general, the effectiveness of all of the above radiation-sensitive compounds can be aided by photosensitizers. These include, for example, anthracene, phenanthrene, pyrene, 1,2-benzanthrene, thiazine, pyrazoline, benzofuran, benzophenone, fluorenone, anthraquinone and coumarin derivatives. Its content is from 0.01 to 5% by weight, based on the weight of the radiation-sensitive mixture.

In particular, triazine derivatives and aromatic compounds containing ring-bonded halogen atoms, in particular bromine atoms, known from West German Patent Application No. 2 610 842 and West German Patent Application No.P3 730 784.3 from the same date are particularly advantageous. is there.

Among the compounds described herein, those having a pKa value of 6 to 10, in particular of the general formula I: [Wherein R represents a hydroxy group or a carboxyl group, R ₁
And R ₂ may be the same or different, and may be a hydrogen atom, a bromine atom, an aryl group, an alkoxy group, an aryloxy group, an alkyl group optionally substituted by a hydroxy group or a fluorine atom, optionally an alkoxy group, an aryl group. Represents an oxy group, a hydroxy group or an aryl group optionally substituted by a fluorine atom, n is 0 to 3, and when n = 0, A is a hydrogen atom, a bromine atom, optionally an alkoxy group, an aryloxy group Represents a hydroxy group, an aryl group or an alkyl group optionally substituted by a fluorine atom, optionally an alkoxy group, an aryloxy group, a hydroxy group, a carboxyl group or an aryl group optionally substituted by a fluorine atom, and n = In the case of 1, A is a single bond, -O-, -S-, SO
_{2 -, - NH -, -} NR 3 -, alkylene group, perfluoroalkylene group, in the case of n = 2, A is And when n = 3, A is And B is Carboxyl group, a substituted carbonyl group, in particular an alkylcarbonyl group or an arylcarbonyl group, carboxyalkyl group or a substituted imide group, R ₃
Represents an alkyl group, in particular a (C ₁ -C ₃ ) alkyl group or an aryl group, especially a phenyl group].

These compounds are preferably decomposed only by high-energy radiation, ie short-wave radiation. In addition to UV-rays this includes in particular electron beams or X-rays.

It is also possible to use polymers of this form in addition to the monomeric radiation-sensitive acid formers. When a monomer initiator is used, its content is 0.01 to 30 relative to the weight of the radiation-sensitive mixture.
% By weight, in particular in the range from 0.4 to 20% by weight.

If a polymeric initiator is used, the polymeric binder can be omitted. Further, the polymer initiator may be mixed with the binder, but it is also possible to react the monomer component of the non-polymerized initiator with the monomer component of the binder to form a cocondensate or a photopolymer. . As a result, their content may exceed the ranges stated for the monomer initiator in relation to the amount of polymer content in the mixture. In particular, a content of from 50% by weight to 100% by weight is used, excluding the content of compounds decomposable by acids.

The radiation-sensitive mixture according to the invention may furthermore comprise a binder which is insoluble in water but soluble in organic solvents and alkalis and which is at least swellable. Such binders include in particular phenolic resins of the novolak type, such as phenol-formaldehyde resins, cresol-formaldehyde resins, co-condensates and mixtures thereof, and phenol and cresol condensates with formaldehyde.

Further, use of a vinyl polymer such as polyvinyl acetate, polymethacrylate, polyacrylate, polyvinyl ether, polyvinylpyrrolidone and a styrene polymer (each of which may be optionally modified with a comonomer) alone or as a mixture with another compound. Can also.

The following may be mentioned in particular: polymers of styrene having alkenylsulfonylaminocarnibonyloxy or cycloalkenylsulfonylaminocarbonyloxy units (EP-A 0 184 804), which are laterally crosslinkable. Polymers containing CH ₂ OR groups such as acrylic acid, methacrylic acid, maleic acid, itaconic acid (European Patent Publication No. 0 184 044), polymers composed of vinyl monomers and alkenylphenol units (European Patent Publication No. No. 0 153 682), polyvinylphenol as a novolac substitute (West German Patent No. 2 322 230), a polymer binder containing phenolic hydroxy groups in the lateral position (European Patent Application Publication No. 0
212 439 and 0 212 440), a styrene-maleic anhydride copolymer (West German Patent Application Publication No. 3).
130 987), polymers comprising active hydrogen-containing polymers and unsaturated (thio) phosphinic acid iso (thio) cyanates (West German Patent Applications P3 615 612.4 and P3 615 613.2), acetic acid Polymers containing vinyl, vinyl alcohol and vinyl acetal units (EP 0 216 083) and poly (vinyl acetal) containing units of hydroxyaldehyde (West German patent application P3 644 162.7).

The amount of binder is generally from 1 to 90% by weight, in particular from 5 to 90% by weight, preferably from 50 to 90% by weight, based on the total weight of the radiation-sensitive mixture.

In addition, dyes, pigments, plasticizers, wetting agents and flow regulators may be added to the radiation-sensitive mixture according to the invention in order to improve flexibility, adhesion and gloss, for example, and also polyglycols, cellulose. Ethers such as ethyl cellulose can also be added.

Radiation-sensitive mixtures according to the invention include solvents such as ethylene glycol, glycol ethers such as glycol monomethyl ether, glycol dimethyl ether, glycol monoethyl ether or propylene glycol monoalkyl ether, especially propylene glycol methyl ether; aliphatic esters such as ethyl acetate, hydroxyethyl acetate, Alkoxyethyl acetate, γ-butyl acetate, propylene glycol monoalkyl ether acetate, especially propylene glycol methyl ether acetate or amino acetate; ethers such as dioxane, ketones such as ethyl ethyl ketone, methyl isobutyl ketone, cyclopentanone and cyclohexanone; dimethylformamide, dimethyl Acetamide, hexamethylphosphoramide N- methyl - pyrrolidone, butyrolactone, it is advantageous that it is dissolved in tetrahydrofuran, and mixtures thereof. Particularly preferred are glycol ethers, aliphatic esters and ketones.

The resulting solution when using the other components of the radiation-sensitive mixture generally contains from 5 to 60% by weight of solids, preferably up to 50% by weight.

Further according to the present invention there is claimed a radiation-sensitive recording material consisting essentially of a substrate and a radiation-sensitive mixture applied thereon.

Suitable substrates are all materials which can constitute or manufacture capacitors, semiconductors, multilayer printed circuits or integrated circuits. Mention may be made in particular of surfaces which are composed of thermally oxidized and / or aluminium-coated silicon materials and which may optionally be further doped, to which all other substrates customary in the semiconductor art, such as nitriding, are mentioned. Also included are silicon, gallium arsenide, and indium arsenide. Further substrates known from the field of liquid crystal display manufacture, such as glass, indium / tin oxide; also metal plates and metal foils, for example made of aluminum, copper or zinc; bimetal and trimetal foils, also metal-deposited non-conductive materials. foil, SiO ₂ coated with aluminum in some cases
-Materials and paper are suitable. These substrates can be subjected to a pre-heating treatment, which can be surface roughened, etched or treated with chemicals to obtain the desired properties, for example to increase hydrophilicity.

In one particular embodiment, the radiation-sensitive mixture may include a fixing agent to improve the adhesion in the resist or between the resist and the substrate. Therefore, in the case of a silicon substrate or a silicon dioxide substrate, an aminosilane type fixing agent such as 3-aminopropyl-triethoxysilane or hexamethyl-
Disilazane is suitable.

Examples of supports which can be used for producing photographic recording coatings such as letterpress, lithographic, screen and gravure printing plates and for producing relief reproductions are aluminum plates, optionally anode plates. Aluminum plates, zinc plates, optionally chromium-treated steel plates and plastic foils or papers, which may be oxidized, ground and / or silicided.

The recording material according to the invention irradiates according to the image. Suitable actinic radiation sources are metal halide lamps, carbon arc lamps, xenon lamps and mercury lamps. Irradiation with high-energy rays such as lasers, electron beams or X-rays is advantageous.
Lasers which may be mentioned are in particular helium / neon lasers, argon lasers, krypton lasers and helium / cadmium lasers.

The coverage is varied in the context of the field of use.
For example, when the radiation-sensitive mixture is applied to a printing plate, an advantageous coverage is 0.5 to 3.5 g / m ² . Generally, the coating thickness is 0.1
-100 μm, especially 1-10 μm.

Further, the present invention relates to a method for producing a radiation-sensitive recording material. Radiation sensitive mixture can be sprayed, flow coated, roll coated,
It can be applied to the substrate by spin coating and dip coating. The solvent is then removed by evaporation, leaving a radiation-sensitive coating on the surface of the substrate. Solvent removal can be facilitated, if necessary, by heating the coating to a temperature of up to 100 ° C. However, it is also possible to first apply the mixture on an intermediate support as described above and then transfer it under pressure to the final support material at an elevated temperature.

The coating is then irradiated according to the image. Usually actinic radiation is used, but UV-rays, X-rays or electron beams are particularly advantageous. Generally, for irradiation, light with a wavelength of 200 to 500 nm is 0.5 to 60 mW /
A UV-lamp emitting at an intensity of cm ² is used. The image pattern is subsequently exposed in the radiation-sensitive coating by development, ie, by treating the coating with a developer that dissolves or removes the irradiated areas of the material.

The developers used are, for example, alkali reagents such as silicates, metasilicates, hydroxides, hydrogen phosphates, dihydrogen phosphates, carbonates or hydrogen carbonates, especially alkali metal or ammonium ions, and also ammonia and A similar solution. The content of these substances in the developer is generally from 0.1 to 15% by weight relative to the weight of the developer, advantageously
0.5 to 5% by weight. Developers that do not contain metal ions are particularly preferred.

The resulting resist structure can be post-cured by DUV-exposure at elevated temperatures.

The acetal present in the radiation-sensitive mixture according to the invention can be prepared by condensing an aldehyde or ketone with an alcohol while azeotropically removing the water of reaction. In another known variant, an aldehyde or ketone is reacted with trimethyl orthoformate to form dimethyl acetal. This compound is then reacted in a second step with an alcohol to give the desired acetal. Unexpectedly, in the process described below, the simultaneous addition of the orthoester and the alcohol to the carbonyl compound in the production of the intended acetal does not produce undesired orthoester transesterification products, but only the desired acetal. It turned out to be obtained.

EXAMPLES The preparation of the novel acid-decomposable compounds present in the radiation-sensitive mixture according to the invention is detailed in the following examples.

Production Example 1 Benzaldehyde-diphenoxyethyl acetal 0.5 g of p-toluenesulfonic acid was added to benzaldehyde 1
Mol, 2 mol of phenoxyethanol and 1.1 mol of trimethyl orthoformate were added with cooling. The mixture was stirred at room temperature for 2 hours. The mixer was then evacuated with a water pump and further stirred at 20 ° C, 40 ° C and 60 ° C for 2 hours each. The reaction mixture was subsequently passed through a thin layer evaporator at 80 ° C. and a pressure of 0.1 torr. If desired, further distillation may be carried out at a suitably elevated temperature in a thin-film evaporator.

The resulting acetal was stirred with Na ₂ CO ₃ , K ₂ CO ₃ or basic aluminum oxide to neutralize the acidic catalyst. The solid component was separated and the filtrate was evaporated in vacuo. Acetal could be used in the recording material in its existing form. It has a melting point of 22-24 ° C., no CO-signal is detected in the IR spectrum and the NMR spectrum (COCl ₃ ) has a δ = 5.76 pmm
Indicates an acetal signal.

Similarly, the acetal and ketanol of the following production examples are shown. The data of the starting components (carbonyl and alcohol components) and the resulting acetal or ketal (NMR signal and boiling point or melting point) are summarized in Table I below: The acetal summarized in Table II for comparison, the alcohol component of which was not used according to the invention, was prepared.

Table III summarizes the present invention with a mixture formula used in _{R- (O-CH 2 CH 2} ) various alcohol components boiling represented by _n -OH (Torr). R = Methyl or n-butyl alcohol and hexanol are compared to these compounds as comparative examples.

Use examples comprising the radiation-sensitive mixture according to the invention and corresponding comparative examples are summarized below. Each quantity is usually given in parts by weight.

Example 1 Coating solution was softened in a softening range of 105 to 120 ° C. Cresole 17 parts by weight Le-formaldehyde novolak benzaldehyde-diphenoxy 5 parts by weight Ethyl acetal (Production Example 1) Tetrabromobisphenol A 4 parts by weight (Dow Chemical) Propylene glycol methyl 74 parts by weight Made from medium ether acetate.

The solution was centrifugally applied at 3000 rpm to a silicon wafer treated with a fixing agent (hexamethyldisilazane). After drying for 30 minutes at 85 ° C. in a circulating air oven, a film thickness of 1 μm was obtained. Irradiation according to the image was carried out with a synchrotron radiation (BESSY, Berlin, air gap 2 mm) in an amount of 32 mJ / cm ² through a gold-on-silicon mask.
The experimental setup is "X-Ray Lithography" by A. Heuberger, Microelec
tronic Engineering 3 . Pp. 535-556 (1985). After a 5 minute dwell time, development was carried out using an alkaline developer of the following composition: sodium metasilicate × 9H ₂ O 5.3 parts by weight trisodium phosphate × 12H ₂ O 3.4 parts by weight sodium dihydrogen phosphate 0.3 parts by weight and deionized water. 91 parts by weight.

A defect-free image containing all the details of the mask is obtained, in this case
0.3 μm lines and grooves were also reproduced without defects. The resist edge also showed an angle of almost 90 ° (taken with a scanning electron microscope SEM).

Examples 2 to 9 The procedure performed is the same as in Example 1, except that the acetal described there is replaced by the acetal from Preparation Examples H2 to H9 in Table I. In this case the following results were obtained in the developer from Example 1 and in a developer free of metal ions (aqueous solution of tetramethylammonium hydroxide): All tested acetals have good developability in both developer types, and also have favorable developer resistance where they were not exposed to more aggressive metal ion-free developers. I was The waiting time from irradiation to development did not affect its dissolving ability unless it was at least 10 minutes and did not exceed 8 hours.

Comparative Examples V1-V4: The treatment was the same as in Example 1, but the acetal used there was replaced by an acid-labile compound from Table II. The results are summarized in Table V.

In order to be able to evaluate the thermal behavior of the radiation-sensitive mixture, the softening points of some mixtures according to the invention were compared with one another. The results from this test are summarized in Table VI.

As shown in these examples and comparative examples, only when the alcohol component used in accordance with the present invention is used, a good development behavior in a metal ion-containing and metal ion-free developer can be obtained by a good thermal deformation. And favorable plasma corrosion behavior. The use of other aldehyde components corresponding to the known state of the art resulted in undesired property spectra without exception.

 ──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-56-99336 (JP, A) JP-A-63-10153 (JP, A) JP-A-63-97945 (JP, A) JP-A 63-99945 97946 (JP, A) JP-A-63-97947 (JP, A) JP-A-64-3647 (JP, A)

Claims (7)

(57) [Claims] A positive radiation-sensitive mixture for producing capacitors, semiconductors, multilayer printed circuits or integrated circuits, comprising a compound which forms an acid under the action of actinic radiation and a compound which can be decomposed by an acid, I: [Wherein R represents a hydrogen atom or an alkyl group, and R ₁ and R ₂ may be the same or different and each represents a hydrogen atom, a hydroxy group, a halogen atom, a cyano group, a nitro group, an alkyl group, an aryl group, or a substituted Represents a carbonyl group, or
R ₁ and R ₂ together form a ring, which may be optionally substituted by R ₁ and / or R ₂ , wherein n is 1-3
Wherein the compound represented by the formula (I) is formed from a compound decomposable by an acid as a decomposition product under the action of an acid. 2. A radiation-sensitive mixture as claimed in claim 1, wherein the acid-decomposable compound used is an acetal or ketal derived from an aldehyde or ketone and an alcohol of the formula I. 3. The radiation-sensitive mixture according to claim 1, wherein the compound decomposable by the acid used is an orthocarboxylic acid ester, orthocarbonate or carboxamide acetal. 4. An aldehyde or ketal component of a compound decomposable by an acid having a boiling point of 155 ° C. or higher and a solubility in an aqueous alkaline developer of 0.1 to 100 g / l.
A radiation-sensitive mixture according to any one of the preceding claims. 5. The radiation-sensitive mixture as claimed in claim 1, wherein the mixture is insoluble in water, but the aqueous alkaline solution contains a soluble binder. 6. A positive-working radiation-sensitive recording material comprising a support and a radiation-sensitive coating, characterized in that the radiation-sensitive mixture according to claim 1 is used. 7. The radiation-sensitive mixture according to claim 1, which is applied to a suitable substrate, which is dried and then irradiated according to the image, and finally contains metal ions or contains metal ions. A method for producing a radiation-sensitive recording material for microelectronic circuits, wherein the development is performed using an aqueous alkaline developer containing no ions.